TAGHAZ, Afghanistan -- Marines here say that the rash of insider
attacks on NATO troops has not impeded operations against the Taliban
nor sown distrust between Afghans and U.S. troops. But they are taking
precautions they had not in the past.

Marines who have been
assisting Afghans here at the headquarters for the Afghanistan Border
Police don't go to the bathroom alone. Someone is assigned to be on the
lookout for suspicious behavior in the Afghan ranks, and guards are now
posted outside when the Marines are eating.

At the highest levels,
military commanders have reinforced the need for deployed Marines and
other coalition troops to have a "guardian angel" in their midst, an
armed individual who watches over his comrades.

"It is absolutely
prudent that if there are four of us sitting here, that one guy is kind
of roaming around and paying attention to things inside and the
outside," a senior Marine official in Afghanistan said. "He's the
Guardian Angel. You and I may know who he is, or we may not know who he
is."

The official requested anonymity so he could speak freely.

The
killing of at least 52 coalition forces this year by Afghan soldiers
and police - or insurgents wearing their uniforms - has made many wary
of the possibility that someone they are working alongside could try to
kill them.

A similar number of Afghan police and soldiers have
died in the same manner. Four Afghan police officers were shot dead
Friday in southern Helmand province in an insider attack, said police
chief Mohammad Toryali. The shooting happened at a police outpost during
a shift change. The killers fled.

U.S. troops have been told by
superiors they must move forward with their training and assistance to
the Afghan National Security Forces, but they are never to let their
guard down.

Maj. Max Hopkins is the commander of the Marine
Border Adviser Team 1 here in Helmand province's Khanashin district. He
said precautions have been implemented but they were not because of a
poor relationship between his team and the Afghans.

He says the Afghan police commander here has rejected new recruits because they did not have good enough references.

"If he doesn't trust them, he doesn't hire them," Hopkins says.

When
a rash of so-called green-on-blue killings this summer occurred, the
commander Lt. Col. Rasoul, who like many Afghans goes by one name,
assembled his forces and stressed there would be stiff consequences if
any member of his unit attacked a Marine, said 1st Lt. John Behrmann, a
Marine adviser.

"He said, 'It's your job to keep them safe. They
left their families in America to come help us,'" Behrmann said. "That
was reassuring."''

In Sangin district, where fighting has been
heavy at times, 1st Battalion, 7th Marines, out of Twentynine Palms,
Calif., emotions ran high when the killings spiked elsewhere.

In
August, a Marine was sharing a security post with an Afghan soldier when
the Afghan chambered a round in his rifle to intimidate the Marine,
said Lt. Col. David Bradney, the battalion commander. The Marine tossed
him from the 11-foot tower and handcuffed him. The Afghan was put in a
detention facility.

Bradney said one key to a secure environment is to show the Afghans that Marines will not tolerate bad behavior of any kind.

"If
some (Afghan soldier) slingshots a round because he doesn't like that
you're not giving him a bottle of water, and you let that go, then what
happens next?" Bradney said. "He walks on post with the round
sling-shotted and shoots you in the gut."

Bradney said the Afghan
soldiers and police in Sangin were mostly cooperative when the Marines
insisted on new security precautions, such as insisting that Afghan
weapons be stored in armories on partnered bases rather than kept in
Afghan possession alone.

"We just told them: 'If we have one
[green-on-blue] incident in Sangin, life as you know it will ... stop,"
he said. "So watch your people, make sure you understand what's at
stake."

Bradney said his battalion was careful to watch out for
trouble before a rise in insider attacks. "Spies" were assigned to
observe Afghan forces and armed "shadows" watched over the Marines, he
said.

Sgt. Maj. Harrison Tanksley, the top enlisted Marine in
Afghanistan, said the attacks made it necessary to "reassess how you are
conducting business" but at the same time it was important to continue
showing trust in the Afghans.

"We cannot afford to let our guard
down anymore," he said. "But, just like we have to respect their
customs, they also have to respect our customs."